Battery operated radio apparatus



Feb. 13, 1940. P. F cs. HOLST BATTERY OPERATED RADIO APPARATUS Filed May 16, 1936 (Ittorneg Patented Feb. 13, 1940 v 1 t UNITED STATES PATENT OFFiCE BATTERY OPERATED RADIO APPARATUS Poul F. G. Holst, ,Oaklyn, N. J., assignor to Radio Corporation of America, a corporation of Delaware Application Ma 1c, 1936, Serial No. 80,098

13 Claims. (01. 250-21) The present invention relates to battery operthe receiver of Fig. 1 for use with A and B bat ated radio apparatus, and more particularly to teries. I a battery operated radio receiving apparatus and Referring to Fig. 1, a radio receiver adapted the like, the tubes of which require filament and for battery operation, comprises a high frequency 5 anode current supply from battery power sources. receiving system indicated at 5 which mayin- ,5

In general, there are at present two common clude the usual. radio frequency amplifier and types of battery power supply means for radio Variable. u ing means and which s ect and other electric discharge tube apparatus, one with afirst detector and combined oscillator deof which is the storage battery and vibrator rectivice 6. The latter is connected with an intermefier generally used in automobile radio receivers, diate frequency amplifier land second detector 10 and the other is the air cell or single cell storage 8 of the diode rectifier type. The diode rectifier A battery and dry B batteries asused with radio is coupled to a Control d 9 in the Same device receivers for camp and other use, beyond the whereby it operates as a first stage audiofrereach of power lines. quency amplifier to supply amplified signals to an 16 It is an object of the present invention, to-proamplifier device I 0 in turn coupled to a push pull 5 vide a battery operated radio apparatus which is output stage comprising ampifier devices H and adapted to use interchangeably, either type oi l2. power supply abovereferred to. The filament or heater supply circuit forthe It is also a further object of the present invarious tubes is preferably grounded to the chas- 20 ventiornto provide an improved cathode heating sis at each filament or heater as indicated at l3 circuit and anode potential supply circuit i'or a. and the filaments or heaters are connected in battery operated radio receiver, whereby it is parallel between ground and a positive supply adapted for economical operation in connection lead I! connected with an input terminal [5. The with a vibrator clevice'and a storage battery, or high voltage B supply for certain of the tubes 255' ordinary A andB batteries. such as the output tubes II and I2 is provided In accordance with the invention, the filament through a lead 16 connected with an input termior heater circuits and the anode circuits of a batnal ll. Lower potential positive B supply for the tery operated receiver are arranged to receive anodes of thevarious tubes and the screen grids supply voltages through separate circuits from is supplied through a lead 18 having an input I difiering supply means or from differing portions terminal l9; Screen grid connections for certain 30 of a storage battery, in which case one oi. said of the tubes are taken through filter resistors 29 circuits includes a vibrator device. and 2| provided with by-pass capacitors 22 It is, therefore, a further object of the invenwhereby the screen grid potential is reduced from tion, to provide an improved power supply system that provided to the anodes and the supply confor a battery operated receiver or the like, which nection is suitably filtered to prevent coupling 35" includes vibrator and filament supply circuits through the common supply means with other operable at differing voltages, the sum of which clrcuits. substantially equals the total voltage available The termlpalboard of the ce includes a from a storage battery and which circuits are ground terminal 3 and a pilot llght terminatu, supplied by differing portions of the battery t the latter bemgconnected through a pair of p1lot 4o prevent coupling between Said Circuita lamps 25 1n parallel, to a ground connection 26. The invention will, however, be better under- The l s for termmals provlded stood from the following description, when conby Sultable i carrymg qonnectlon elements sidered in connection with the accompanying for i g g fi fi fg p drawings and its scope will be pointed out in plural y ea -connec e erewl as md cated and comprising a posit1ve A battery supply the appended 3 lead 28 enclosed in an outer metallic shield 29 F drawmg f 1 is schematm extending from the'plug through to two terminal cult dmgram of rad) receiver embodying the ends 30 and 3|. The positive lead 28 is connected invention, with the terminal l5 and also with the terminal 50 E- 2 S a detall 0111311111 diagram Showing 00 24 while the negative outer shield 29 is connected nections with a storage battery for the system of with the terminal 23. In this manner the leads Fig. 1 and, 30 and 3| may be connected to any suitable two Fig. 3 is a similarschematic circuit diagram volt source or filament supply, such as a single showing a modification of the supply circuits for cell of a 6 volt storage battery, at the terminals 55 +4 and +6, for example, as indicated in the drawing. A switch 32 is provided for opening the positive lead 38 to ole-energize the'heater or filament circuit.

The B supply potentials are derived from a vibrator rectifier device comprising a step-up transformer 35 having a vibrator armature 36 connected to ground 31 and alternately to primary and secondary contacts 38', wherebythe.

the dot and dash line 44.- The vibrator may be mounted in the receiver or close to it butis insu lated therefrom. The lead 43 is connected with.

theground lead 3| which is connected with the shield 29 and thence to the chassis ground terminal 23. This arrangement prevents'vibrator disturbancesfrom entering the receiver chassis.

I chassis 44 of the vibrator unit. The lead 43 is The negative vibrator supply lead 42 is connected with the negative terminal of the battery, and includes a fuse-46 and a switch 4! connected. in circuit through shielded leads 48, the shield being indicated at 49. This is insulated from also included inthis shield.

'I'he'switch 41, through one of the leads 48, is

. connected with the input lead 4| for the vibrator,

mary 5!] of the transformer 35' alternatelyi through each half thereof asv a result'of the operation of the armature 36; As the operation of such units is well known and understood further description is believed to be unnecessary.

For simultaneous operation, the switches 41 and 32 are interconnected by mechanical means indicated by the dotted connection 5| so that the vibrator and the filament supply may both be controlled by commonmeans. Y

The connections for the leads 42, 43, 30 and 3! with a storage battery 53' are indicated in Fig. 3. The battery has a negative terminal 54, a 6 volt positive terminal 55 and terminals 56 on the two cells joined by the strip 56 which are at 4 volts positive with respect to the negative terminal 54.

In case that the receiver filament or heater load, which is applied to the-cellbetwee'n the terminals 55 and 56, is not equal to the load imposed by the vibrator across the two cells in series between the terminal 54 and the terminals 56, a load resistor 58may be connected across the fila ment circuit preferably at the switchr32 between the lead 28 and the shield lead 29 whereby the battery is uniformly loaded anddischarge rate in all of the cells is substantiallythe same. In

certain applications'this loadcompensating resistor may not be necessary. *0 battery leads for Small nals on the receiver, to the battery or potential tery whereby a difference of source, with a grounded shield lead. about the supply lead forming one of the filament conductors which is connected to the chassis ground. This shield lead is connected to an intermediate point on the battery which supplies a positive potential of 4 volts and the ungrounded filament supply lead is connected to the terminal of the battery which supplies a positive potential of 6 volts thereby establishing on the filament circuit a difference in potentialof two volts.

The remainder of the battery voltage, of four volts, is utilized in the vibrator device by connect- .ing the.--vibrator ground lead to the positive 4 volt terminal of the battery in common with the ground connection for the filament circuit. The negativeterminal of the vibrator supply circuit is connected with the negative terminal of the batvolts applied to the vibrator. The filament circuit and the vibrator supply circuit are shielded one from the other thereby. preventing interference from vibratoractionfrorn reaching the filament circuit. This is further prevented by a radio frequency filter BB in the vibrator input circuit lead 4! and a second filter iil in the vibrator output circuit which'is connected with the output leads 35 and 453. These are preferably high or radio'frequency filters effectiveagainst ultra-short waves which are found to be present when operating vibrators of the type shown in the drawing. 7

In order further to provide 'eiiective shielding, the shield 48 is connected through a lead 52 with the receiver chassis by means of a terminal 63 connected to the chassis as indicated by the ground connection 64. The vibrator frame or round 44 is not connected with the shield 49. The only-ground connection to the receiver is through the lead 43. I

All of the leads provided'in connection-with the terminals'IQ, 23, !5, I! and 24 may be carried by a plug indicated'by the dotted outline 55' usually provided by suitable clips indicated by the arrow connections inFig. 2.

Referring now'to'Fig: 3, 'A'and B'battery connections for the receiver may readily be provided by inserting a second plug 66 in place of the plug 65, the plug fifi' carrying terminal connections 61 to H inclusive which are connected through a switch 12 with A and B battery leads, the A battery leads being indicated at 73', l4, l5 and the B battery leads being indicated at 16 and Ti. the leads" including a fuse l8 and the leads 14 including a series resistor 79.

The switch may'comprise a series of contacts arranged around the periphery of a movable insulating element, which contacts may be con nected by rotation of the element, by contact segments indicated at 80, 8! and 82. The seg ments are shown in the on positions, and are movable tothe off position bycounter-clockwise rotation from the positions shown.

As shown, the segment 82 serves to connect a contact 83 with a contact 84 completing a circuit connection between the A battery' positive lead 13 and the positive A battery terminal 15 of the receiver through the lead 69. Since the negative A battery lead 15 is. connected with the lead 58 and th'e" negative A battery terminal 23, the filament or heater circuit is completed through the A battery, which may be of any suitable type adapted to be connected between the leads [5 and eithercfthe leads 13 or -14"depending"upon the voltage of the A battery. For a storage battery cell connection, with the lead 13 at 2 volts, or air cell battery connection with the lead 14 at 2.5 volts, the series resistor Isis efiective to limit the voltage in the latter connection.

At the same time the A battery circuit is com pleted, the'B battery circuit is completed through the segment 8!, connectingterminals 85 and, to provide a connection between the B battery supply leads ST and Hi with the B battery leads 11. Thepilot or dial lamp terminal 24 is finer gized by further rotation of the control switch to the right, in a clockwisedirection, 'to cause the segment 86 to connect'the terminals 81 and 88 providing a connection between the leads H and J3. The A battery and B battery connections tube circuits are maintained throughadditional contact. provided by the contact 89 and 90 with the terminals 86 and 83.

For simplifying the 3 battery connections, it

will be seen that the screen grid and low voltage anode circuit terminal I 9 is connected with the I high voltage B terminal I! through the lead in in connection with the lead 61 whereby a single B battery lead TI and the positive supply voltage is required. As A and B battery connections are well known the same are not illustrated in connection with the batteries.

The switch '12 may be arranged in any suitable manner other than that shown, to provide an open circuit condition in the A and B battery leads for the on position and having two closed circuit or on positions, one of which provides additional contacts for energizing the pilot lamp circuit, whereby the pilot or dial lamp may be utilized for tuning, and then its currentinay be cut off to economize on battery consumption while listening to aprogram. With this arrangement, any similar circuit in the receiver apparatus may be energized and -de-energize'd while the apparatus is energized. This is a desirable feature of the potential supply system since it further adapts the receiver connections for ordinary A battery operation in amanner to reduce the current drawn therefrom ver the longer periods of operation when listening to a selected program.

Since the vibrator supply source is not used, the leads in connection with the plug. 66 are not shielded and accordingly the chassis ground connection terminal 63 is not utilized. v I

It will be noted that in this case, the negative A battery lead 15 and the negative B battery lead are connected together, through the lead 68, to the common grounded chassis terminal 23 as in the preceding circuit, whereby the change to vibrator operation involves no internal or external changes in the wiring of the receiver.

This circuit arrangement, as shown and described herein, has the added advantage that for vibrator and storage battery operation, the same separation of A and B supply sources is obtained as in connection with A and B batteries, because of the fact that the filament circuits of a receiver are connected to a separate portion of the storage A battery from that to which the vibrator is connected. This connection arrangement further isolates the filament and vibrator circuits, and results in a material reduction of noise in a battery operated receiver when connected for vibrator operation, since ripple currents in the vibrator circuit are entirely confined to a separate supply source and circuit but without requiring extra battery equipment.

Furthermore this type of receiver with interv volving no degree of skill on the part of the user to make the changes from one mode of operation 'to the other, and thereby greatly extending the usefulness of the automobile or battery type of, receiver without complication in the .matter of controls and adapting devices.

In a preferred embodiment of the invention the vibrator device may be built into and insulated romv the receiver chassis in the manner, indicated, and may then, be, connected in use only when a storage battery supply is available.

I claim as my invention:

1. In a battery operated signal amplifyin apparatus including a lurality of electric discharge devices. a cathode heating circuit having a chassis ground connection and a common supply lead provided with external terminal means, means providing anode and screen grid supply connections for saida paratus having external terminal means associated with said first-named terminal means, a vibrator potential supply device connected with said last-named terminals, said vibrator device being designed tooperate witha potential of substantially four volts and said filament heating circuit bein designed to operate. with a potential of substantially two volts, whereby said vibrator and cathode heating circuits may be connected with the terminals of a storage battery with a commonconnection at an intermediate tap thereon, filament circuit supply connections for said first named terminals including a shielded conductor, and separate supply leads for said vibrator device.

2. A system in accordance with claim 1 further characterized by the fact thatmeansare pro- 45 vided for equalizing the battery load provided by the cathode heating circuit and vibrator supply circuit.

3. A system in accordance with claim 1 further characterized by the fact that external filament 50 heating circuit connections and vibrator supply connections therefor are provided by a detachable plug and. that a seconclplug is provided for attaching A' and B battery leads to the same terminals for A and B battery operation.

4. A battery operated radio receiver having A and B battery supply terminals adapted for operation in connection with a storage battery and a vibrator B potential supply device, cathode heating current supply leads connected with said 60 terminals, said leads being shielded, supply leads for said vibrator device, means providing one circuit for connecting said vibrator device with a portion of a storage battery, means providing a separate circuit for connecting said cathode 65 heating circuit with a different portion of said battery whereby the cathode heating circuit load and vibrator load are apportioned to differing portions of said battery, and means providing a common ground connection for said circuits at an intermediate tap point on said battery.

5. In combination, battery operated radio apparatus or the like, adapted for operation in connection with A and B batteries for cathode heat ing and plate potential supply, respectively, and

1 alternatively in connection only: with. a storage battery for; cathode; heatingand said battery in conjunction: with avibrator Bsupply device for plate, potential supply, -means-providing an A supplylead with said-receiverfor cathode heating and-separate vibratorsupply circuits, said -mon intermediate tap connection for said cirmeans further being. arranged. to provide a com- ;cuits on said storage-battery; whereby the load thereon provided-by the vibrator device andthe cathode-heating circuit-may be .ap-plied to differing portions, thereof, and thereby. separating thepotentialsources forvi-brator and cathode heating. within the a battery.

6. .Batteryoperated radio apparatus as defined in claim 5, further-characterized by the fact that .means providing A and Bbattery connections include a switch and apilot lamp circuit inthe apparatus which may beenergizedand. de-energized through operation of the switch while the which provides a shield for. the other, connected .30.

with.saidcathodeheating circuit, said vibrator and cathode, heating circuit being designed to operate at difierent potentials, the sum of which is eq al substantially to the potential supplied by said storagebattery.

.for storage battery and vibrator operation, and

8. A battery operated receiving systemin accordance with claim '7, further characterized by the factv that the vibrator device is insulated from the receiver chassis and is interconnected therewith through acommon ground connection to an intermediate tap on the battery through said, shield lead.

9. A battery operated receiver in accordance with claim 7,-.further characterized by the fact that the battery power connections thereto are the same for both A-and B battery operation and meansproviding an interchangeable plug connection therewith providing either type of con- .nection.

v having separate cathode heating and anode cir- 10. In combination, a battery operated receiver cuits, means for supplying operating current to said circuitsfrom a storage battery, comprising a vibratorpower supply device connected with saidanodecircuits and-haying a pairofwlow voltagesupplyv leads, a :pairfof leads connected with said cathode heating circuit, said vibrator device and cathode,heating'circuit" being designed. to

operateat differingpotentials, the sum of which is equal to the potential supplied by said storage battery, psaid cathode heating circuit and vibrator supply circuit being thereby adapted to be'connected in common to-an intermediate terminal on the batterysource of supply, and means for grounding said terminal to the receiver chassis comprising a shield for one of the cathode heating circuit supply leads, which shield provides the other conductor.

11. Ina battery operated receiving system, means providing anode potentials including a battery anda vibrator device operating from a certain portion thereon, means providing cathode heating current including a differing portion of the same battery, and saidanode potential supply means and said cathode heating current supply means being interconnected only at said battery;

-12. In combination, a battery-operated receiver having separate cathode heating and anode circuits,=and means for supplying operating current to said circuits from a storage battery comprising a vibratorpowensupply device connected low voltage supply leads, one of which is connected with one side of said cathode heating circuit at the battery end thereof, said vibrator and cathode heating circuits being designed to operate at differing potentials, the sum of which is equal substantially to the .potential supplied by said storage battery.

l3. The combination, with radio receiving apparatus having a cathode heating circuit and a ,plate circuit,- of a power supply circuit system vfor supplyingelectric current to said circuits comprising a storage battery having a plurality of cells connected together in series, voltage step-up means having. a. low-.voltage input in circuit connection with certain .of the cells of said storage. battery and a high-voltage output. ;in circuit connection with the plate circuit of said radio receiving apparatus, and circuit connectionsconnecting the cathode heating circuit of said radio. receiving apparatus with certain of withsaid anode circuits and having a pair of the cells of said storage batteryother than the 5 cellor cells thereof in circuitconnection with v the inputof said voltage step-up means.

POUL F. G. HOLST. 

